Orodispersible tablet containing estetrol

ABSTRACT

The invention provides an orodispersible solid pharmaceutical dosage unit having a weight between 30 and 1,000 mg, said dosage unit containing at least 100 μg of an estetrol component selected from estetrol, estetrol esters and combinations thereof; wherein the solid dosage unit can be obtained by a process that comprises: providing a loading liquid comprising organic solvent; estetrol component and optionally one or more other pharmaceutically acceptable ingredients; mixing 1 part by weight of the loading liquid with 0.5-20 parts by weight of carrier particles to produce wet particles; removing organic solvent from the wet particles to produce loaded particles; optionally mixing the loaded particles with one or more tabletting excipients; and forming the loaded particles or the mixture of the loaded particles and the one or more tabletting excipients into a solid dosage unit. The solid dosage unit is easy to manufacture and perfectly suited for sublingual, buccal or sublabial administration.

TECHNICAL FIELD OF THE INVENTION

The present invention provides an orodispersible solid pharmaceutical dosage unit having a weight between 30 and 1,000 mg, said dosage unit containing at least 100 μg of an estetrol component selected from estetrol, estetrol esters and combinations thereof.

The invention also provides a process of preparing the aforementioned solid dosage unit.

Furthermore, the invention relates to the use of the solid dosage unit in medical treatment, female hormone replacement therapy and female contraception, said use comprising sublingual, buccal or sublabial administration of the solid dosage unit.

BACKGROUND OF THE INVENTION

Estetrol is a human steroid, produced by the fetal liver during pregnancy only. This natural hormone was discovered in urine of pregnant women by Diczfalusy and coworkers in 1965. Estetrol has the structure of an estrogenic steroid with four hydroxyl groups. Estetrol is synthesized in the fetal liver from estradiol and estriol by the two enzymes 15α- and 16α-hydroxylase. After birth the neonatal liver rapidly loses its capacity to synthesize estetrol because these two enzymes are no longer expressed.

Estetrol reaches the maternal circulation through the placenta and was already detected at nine weeks of pregnancy in maternal urine. During the second trimester of pregnancy high levels were found in maternal plasma, with steadily rising concentrations of unconjugated estetrol to about 1 ng/mL (>3 nmol/L) towards the end of pregnancy. So far the physiological function of estetrol is unknown. The possible use of estetrol as a marker for fetal well-being has been studied quite extensively. However, due to the large intra- and inter-individual variation of maternal estetrol plasma levels during pregnancy this appeared not to be feasible.

Since 2001 estetrol has been studied extensively. In humans estetrol was shown to have a high and dose-proportional oral bioavailability and a long terminal elimination half-life of about 28 hours. Results from in vitro studies showed that estetrol binds highly selective to the estrogen receptors with preference for the ERα form of the receptor, unlike the estrogens ethinyl estradiol and 17β-estradiol. Also in contrast with ethinyl estradiol and especially with 17β-estradiol, estetrol does not bind to sex hormone binding globulin (SHBG) and does not stimulate the production of SHBG in vitro.

The properties of estetrol have also been investigated in a series of predictive, well validated pharmacological in vivo rat models. In these models, estetrol exhibited estrogenic effects on the vagina, the uterus (both myometrium and endometrium), body weight, bone mass, bone strength, hot flushes and on ovulation (inhibition). All these effects of estetrol were dose-dependent with maximum effects at comparable dose levels. Surprisingly, estetrol prevented tumour development in a DMBA mammary tumour model to an extent and at a dose level similar to the anti-estrogen tamoxifen and to ovariectomy. This anti-estrogenic effect of estetrol in the presence of 17β-estradiol has also been observed in in vitro studies using human breast cancer cells.

Buccal, sublingual or sublabial administration of estetrol is mentioned in a number of patent applications, including WO 2002/094275, WO 2002/094276, WO 2002/094278 and WO 2003/018026. Estetrol containing dosage units for buccal, sublingual or sublabial administration are not described in these publications.

WO 2010/033832 describes an oral dosage form comprising an estriol compound and a pharmaceutically acceptable matrix material, wherein the oral dosage form releases at least about 90% of the estriol compound in a time of less than about 300 seconds when contacted with saliva of the buccal and/or sublingual cavity.

US 2007/286829 describes an orally administered solid dosage form capable of delivering ethinyl estradiol with improved bioavailability, said solid dosage form comprising (i) about 0.5 μg to about 50 μg of ethinyl estradiol and (ii) an oral dissolution enhancing carrier that provides for at least 15% absorption of the ethinyl estradiol through the oral mucosa when said solid dosage form is orally administered to the patient with 2 ounces of water or less.

U.S. Pat. No. 6,117,446 describes a buccal dosage unit for administering a combination of steroidal active agents, comprising a compressed tablet of a bioerodible polymeric carrier and therapeutically effective amounts of an androgenic agent selected from testosterone and pharmacologically acceptable esters thereof, a progestin and an estrogen. The examples describe buccal dosage units that were prepared by thoroughly mixing the following components: estrogen, progestogen, androgen, polyethylene oxide, carbomer and magnesium stearate. Next, the mixture was granulated by means of fluid bed granulation and the granulate so obtained was pressed into tablets.

Oral dosage units containing estetrol have been described in several patent publications.

WO 2002/094276 describes a pharmaceutical composition for use in a method of hormone replacement therapy, which method comprises administering to a person in need of such a therapy an effective amount of estetrol, said composition containing virtually no progestogen or anti-progestin. WO 2002/094276 describes the preparation of estetrol tablets having a weight of 185 mg, containing 1.5 mg estetrol, on the basis of the following formulation:

mg Estetrol 1.5 Polyvinylpyrrolidone (Kollidon 25 ® ex BASF) 12.5 Lactose 135.795 Microcrystalline cellulose (Avicel PH 101 ®) 26.25 Glyceryl palmitostearate (Precirol ®) 2.775 Anhydrous colloidal silica (Aerosil 200 ®) 1.0 Crospovidone (Polyplasdone XL ®) 4.0 Coloring agent 0.18

WO 2002/094275 describes the use of an estetrol in a method of increasing libido in a woman, said method comprising administering to said woman an effective amount of estetrol. Oral administration is mentioned as a suitable mode of administration. This patent application describes the same estetrol tablet as WO 2002/094276.

WO 2002/094279 describes the use of estetrol in a method of contraception in mammalian females, which method comprises the oral administration of said estrogenic component and a progestogenic component to a female of childbearing capability in an effective amount to inhibit ovulation. The following formulation for a 185 mg estetrol tablet is described in this international patent application.

mg Estetrol 1.5 Levonorgestrel 0.15 Polyvinylpyrrolidone (Kollidon 25 ® ex BASF) 13.5 Lactose 135.645 Microcrystalline cellulose (Avicel PH 101 ®) 26.25 Glyceryl palmitostearate (Precirol ®) 2.775 Anhydrous colloidal silica (Aerosil 200 ®) 1.0 Crospovidone (Polyplasdone XL ®) 4.0 Coloring agent 0.18

WO 2003/041718 describes the use of estetrol in a method of hormone replacement in mammals, which method comprises the oral administration of estetrol and a progestogenic component to a mammal in an effective amount to prevent or treat symptoms of hypoestrogenism. This patent application describes the same estetrol tablet as WO 2002/094279.

WO 2007/081206 describes the use of estetrol in a method of treating an acute vascular disorder in a mammal, said method comprising orally administering to said mammal, upon demand, an effective amount of the estetrol to the mammal. This patent application describes the preparation of hard gelatine capsules, containing 100 mg estetrol and 25 mg sildenafil citrate per capsule.

WO 2008/156365 describes the use of estetrol in the treatment of Meconium Aspiration Syndrome (MAS) in a newborn infant, said treatment comprising administering an effective amount of estrogen to said newborn infant within 7 days after birth. The international patent application describes a suppository for use in newborn infants comprising at least 1 μg of estrogen, said suppository further being characterized by a maximum diameter of less than 10 mm and a weight of less than 0.5 g. The excipient contained in the suppository may be based on lipid material that melts at body temperature or it may be based on a hydrophilic component that dissolves or disintegrates when it comes into contact with water.

SUMMARY OF THE INVENTION

The present invention provides an orodispersible solid pharmaceutical dosage unit containing an estetrol component. The dosage unit rapidly releases the estetrol in aqueous environment. The solid dosage unit is easy to manufacture and perfectly suited for sublingual, buccal or sublabial administration. Sublingual, buccal and sublabial administration each offer the advantages that the estetrol component does not have to pass through the digestive system and avoids first-pass liver exposure. Furthermore, these modes of administration provide a rapid onset of action.

The solid dosage unit according to the present invention has a weight between 30 and 1,000 mg and contains at least 100 μg of an estetrol component selected from estetrol, estetrol esters and combinations thereof. This solid dosage unit is obtainable by a process comprising:

-   -   providing carrier particles having a volume median diameter of         10 μm to 400 μm;     -   providing a loading liquid comprising at least 50 wt. % of         organic solvent selected from methanol, ethanol, iso-propanol,         acetone and combinations thereof; 1-50 wt. % of estetrol         component and 0-49 wt. % of one or more other pharmaceutically         acceptable ingredients;     -   mixing 1 part by weight of the loading liquid with 0.5-20 parts         by weight of the carrier particles to produce wet particles;     -   removing organic solvent from the wet particles to produce         loaded particles;     -   optionally mixing the loaded particles with one or more         tabletting excipients; and     -   forming the loaded particles or the mixture of the loaded         particles and the one or more tabletting excipients into a solid         dosage unit.

Rapid and complete dissolution of the estetrol component into saliva is essential for efficient delivery of the component via sublingual, buccal or sublabial administration of the solid dosage unit. The inventors have unexpectedly found that the estetrol component is rapidly released and dispersed into saliva and absorbed through the mucosal lining of the oral cavity if it is present in the solid dosage unit in the form of very small particles.

The invention also provides a process of preparing the aforementioned solid dosage unit, said process comprising the steps of:

-   -   providing carrier particles having a volume weighted average         particle size of 10 μm to 400 μm;     -   providing a loading liquid comprising at least 50 wt. % of         organic solvent selected from methanol, ethanol, iso-propanol,         acetone and combinations thereof; 1-50 wt. % of estetrol         component and 0-49 wt. % of one or more other pharmaceutically         acceptable ingredients;     -   mixing 1 part by weight of the loading liquid with 0.5-20 parts         by weight of the carrier particles to produce wet particles;     -   removing organic solvent from the wet particles to produce         loaded particles;     -   optionally mixing the loaded particles with one or more         tabletting excipients; and     -   forming the loaded particles or the mixture of the loaded         particles and the one or more tabletting excipients into a solid         dosage unit.

The production of the estetrol-containing loaded particles in this process may suitably be carried out, for instance, in a fluidized bed granulator.

BRIEF DESCRIPTION OF THE FIGURE

FIG. 1 illustrates the manufacturing process flow chart used in Example 2.

DETAILED DESCRIPTION OF THE INVENTION

A first aspect of the invention relates to an orodispersible solid pharmaceutical dosage unit having a weight between 30 and 1,000 mg, said dosage unit containing at least 100 μg of an estetrol component selected from estetrol, estetrol esters and combinations thereof; wherein the solid dosage unit can be obtained by a process comprising:

-   -   providing carrier particles having a volume weighted average         particle size of 10 μm to 400 μm;     -   providing a loading liquid comprising at least 50 wt. % of         organic solvent selected from methanol, ethanol, iso-propanol,         acetone and combinations thereof; 1-50 wt. % of estetrol         component and 0-49 wt. % of one or more other pharmaceutically         acceptable ingredients;     -   mixing 1 part by weight of the loading liquid with 0.5-20 parts         by weight of the carrier particles to produce wet particles;     -   removing organic solvent from the wet particles to produce         loaded particles;     -   optionally mixing the loaded particles with one or more         tabletting excipients; and     -   forming the loaded particles or the mixture of the loaded         particles and the one or more tabletting excipients into a solid         dosage unit.

The term ‘estetrol’ as used herein refers to 1,3,5 (10)-estratrien-3,15α,16α,17β-tetrol or 15α-hydroxyestriol as well as hydrates of estetrol, e.g. estetrol monohydrate.

The term ‘orodispersible dosage unit’ as used herein refers to a dosage unit that is designed to rapidly disintegrate in the oral cavity when it comes into contact with saliva and to disperse the estetrol component into the saliva so it may be absorbed through the mucosal lining of the oral cavity.

The terms ‘pharmaceutically acceptable ingredients’ as used herein include both pharmaceutically acceptable excipients and pharmaceutically active ingredients other than the estetrol component, as further defined below.

The term ‘sublingual’ as used herein refers to the pharmacological route of administration by which the estetrol component diffuses into the blood through tissues under the tongue.

The term ‘buccal’ as used herein refers to the pharmacological route of administration by which the estetrol component diffuses into the blood through tissues of the buccal vestibule, the area inside the mouth between the lining of cheek (the buccal mucosa) and the teeth/gums.

The term ‘sublabial’ as used herein refers to the pharmacological route of administration by which the estetrol component is placed between the lip and the gingiva. The term “granulation” as used herein, unless indicated otherwise, relates to a process in which primary powder particles are made to adhere to form larger, multiparticle entities called “granules”.

The term ‘tabletting excipient’ as used herein refers to a pharmaceutically acceptable excipient that can be used in the manufacture of solid dosage units, such as tablets.

The particles size distribution of particulate materials used and produced in the present process, may suitably be determined by means of laser diffraction.

Unless indicated otherwise, all percentages mentioned herein are percentages by weight.

Examples of solid dosage units encompassed by the present invention include tablets, dragees, lozenges and films. In accordance with a preferred embodiment, the dosage unit is a tablet, most preferably a compressed tablet.

The solid dosage unit typically has a weight between 40 and 500 mg, more preferably between 50 and 300 mg, and most preferably between 70 and 150 mg.

The solid dosage unit preferably comprises at least 1 wt. %, more preferably 2-40 wt. % and most preferably 2.2-15 wt. % of the estetrol component.

The amount of the estetrol component contained in the solid dosage unit preferably lies within the range of 0.3-100 mg, more preferably of 0.5-40 mg and most preferably of 1-20 mg.

The estetrol component of the present invention preferably is selected from the group consisting of estetrol, esters of estetrol wherein the hydrogen atom of at least one of the hydroxyl groups has been substituted by an acyl radical of a hydrocarbon carboxylic, sulfonic acid or sulfamic acid of 1-25 carbon atoms; and combinations thereof. Even more preferably, the estetrol component is estetrol (including estetrol hydrates). Most preferably, the estetrol component contained in the dosage unit is estetrol monohydrate.

The solid dosage unit of the present invention offers the advantage that the estetrol component is rapidly released when the dosage unit is introduced into the oral cavity and comes into contact with saliva. The rate of release of the estetrol component from the dosage unit can suitably be determined using the dissolution test described in the Examples, or a disintegration test according to Ph. Eur. 2.9.1 (“Disintegration of tablets and capsules”) and USP <701> (“Disintegration”), also described in the Examples. The solid dosage unit of the present invention, when subjected to the aforementioned dissolution test, typically releases at least 50%, more preferably at least 70% and most preferably at least 80% of the estetrol component after 5 minutes. The solid dosage unit of the present invention, when subjected to the aforementioned disintegration test, typically disintegrates within less than 5 minutes, more preferably within less than 2 minutes, still more preferably within less than 1.5 minutes, still more preferably within less than 1 minute, still more preferably within less than 45 seconds, and most preferably within less than 30 seconds.

Excipients that may suitably be incorporated in the solid dosage unit include water-soluble carbohydrate, diluents/fillers (e.g. calcium salts, microcrystalline cellulose), binders, disintegrating agents, mucoadhesive agents, flavouring, colouring, glidents, lubricants and combinations thereof.

The solid dosage unit of the present invention preferably contains 30-99.9 wt. % of water-soluble carbohydrate selected from maltose, fructose, sucrose, lactose, glucose, galactose, trehalose, xylitol, sorbitol, erythritol, maltitol, mannitol, isomalt and combinations thereof. More preferably, the water-soluble carbohydrate is selected from lactose, mannitol, erythritol and combinations thereof. Even more preferably, the water-soluble carbohydrate is selected from mannitol, erythritol and combinations thereof. Most preferably, the water-soluble carbohydrate is mannitol.

The solid dosage unit preferably contains at least 20 wt. % mannitol. More preferably, the dosage unit contains 30-70 wt. % mannitol, most preferably 40-60 wt. % mannitol.

The water-soluble carbohydrate is preferably contained in the dosage unit in crystalline form.

The dosage unit preferably contains 0.1-20 wt. %, more preferably 1-5 wt. % of a binder selected from cellulose derivatives, polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and combinations thereof. Preferably, the binder employed in the dosage unit is a cellulose derivative.

Examples of cellulose derivatives that may be employed in the dosage unit as binder include hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose, hydroxypropylmethyl cellulose, methylcellulose, ethylcellulose, carboxymethyl cellulose and combinations thereof. Most preferably, the cellulose derivative employed is ethylcellulose.

According to another preferred embodiment, the dosage unit contains 0-20 wt. %, more preferably 0.2-10 wt. % of a disintegrating agent selected from modified starches (e.g. sodium salt of carboxymethyl starch), crosslinked polyvinylpyrrolidone, crosslinked carmellose and combinations thereof.

The loaded particles typically constitute 20-99.9 wt. % of the oral dosage unit. More preferably, these loaded particles represent 50-99.8 wt. %, most preferably 60-99.7 wt. % of the oral dosage unit.

Typically, the loaded particles containing the estetrol component have a volume weighted average diameter of 100-4,000 μm, more preferably of 150-1,000 μm and most preferably of 200-600 μm.

The loaded particles typically contain 1-50 wt. % of the estetrol component. Even more preferably, the loaded particles contain 5-30 wt. %, most preferably 10-20 wt. % of the estetrol component.

The loaded particles preferably contain at least 20 wt. % of the water-soluble carbohydrate as defined herein before. Even more preferably, these loaded particles contain at least 40% and most preferably at least 50% of the water-soluble carbohydrate.

Besides the loaded particles, the solid dosage unit of the present invention may suitably contain 0.1-80 wt. %, more preferably 0.2-50 wt. % and most preferably 0.3-40 wt. % of tabletting excipients. Examples of tabletting excipients that may suitably be present in the dosage unit include filler, disintegrating agents, mucoadhesive agents, flavouring, colouring, glidents, lubricants and combinations thereof.

The tabletting excipients in the dosage unit preferably contain, calculated by weight of said tabletting excipients, at least 30 wt. %, more preferably at least 50 wt. %, most preferably at least 70 wt. % of one or more excipients selected from lactose, mannitol, xylitol, microcrystalline cellulose, starch, croscarmellose sodium, polyvinyl pyrrolidone and combinations thereof. According to one particularly preferred embodiment, the tabletting excipients contain at least 50 wt. % mannitol. In accordance with another preferred embodiment, the tabletting excipients contain at least 50 wt. % lactose.

The solid dosage unit may contain one or more other pharmaceutically active ingredients besides the estetrol component. Examples of such other pharmaceutically active ingredients include steroid hormones. The solid dosage unit of the present invention preferably contains 0.05-10 mg, more preferably 0.1-5 mg of one or more progestogens, preferably one or more progestogens selected from progesterone, levonorgestrel, norgestimate, norethisterone, norethisteron-acetate (NETA), dydrogesterone, drospirenone, 3-beta-hydroxydesogestrel, 3-keto desogestrel (=etonogestrel), 17-deacetyl norgestimate, 19-norprogesterone, acetoxypregneno lone, allylestrenol, anagestone, chlormadinone, cyproterone, demegestone, desogestrel, dienogest, dihydrogesterone, dimethisterone, ethisterone, ethynodiol diacetate, flurogestone acetate, gastrinon, gestodene, gestrinone, hydroxymethylprogesterone, hydroxyprogesterone, lynestrenol (=lynoestrenol), medrogestone, medroxyprogesterone, megestrol, melengestrol, nestorone, nomegestrol, nomegestrol-acetate (NOMAC), norethindrone (=norethisterone), norethynodrel, norgestrel (includes d-norgestrel and dl-norgestrel), norgestrienone, normethisterone, progesterone, quingestanol, (17alpha)-17-hydroxy-11-methylene-19-norpregna-4,15-diene-20-yn-3-one, tibolone, trimegestone, algestone acetophenide, nestorone, promegestone, 17-hydroxyprogesterone esters, 19-nor-17hydroxyprogesterone, 17alpha-ethinyl-testosterone, 17 alpha-ethinyl-19-nor-testosterone, d-17beta-acetoxy-13beta-ethyl-17alpha-ethinyl-gon-4-en-3-one oxime and prodrugs of these compounds. Preferably the one or more progestogens used in accordance with the present invention is selected from the group consisting of progesterone, desogestrel, etonogestrel, gestodene, dienogest, levonorgestrel, norgestimate, norethisterone, norethisteron-acetate (NETA), nomegestrol, nomegestrol-acetate (NOMAC), drospirenone, trimegestone, nestorone and dydrogesterone.

The solid dosage unit according to the present invention preferably contains 0.05-100 mg, more preferably 0.1-50 mg of one or more androgens, preferably one or more androgens selected from testosterone, dehydroepiandrosterone (DHEA); DHEA-sulphate (DHEAS); testosterone esters (e.g. testosterone undecanoate, testosterone propionate, testosterone phenylpropionate, testosterone isohexanoate, testosterone enantate, testosterone bucanate, testosterone decanoate, testosterone buciclate); methyltestosterone; mesterolon; stanozolol; androstenedione; dihydrotestosterone; androstanediol; metenolon; fluoxymesterone; oxymesterone; methandrostenolol; MENT and prodrugs of these compounds. Most preferably the one or more androgens are selected from the group consisting of testosterone, DHEA and MENT.

Another aspect of the present invention relates to the use of the aforementioned solid dosage unit in medical treatment, in female hormone replacement therapy or in female contraception, said use comprising sublingual, buccal or sublabial administration of the dosage unit. Examples of medical treatment in which the solid dosage unit of the present invention may suitably be used include treatment of osteoporosis and estrogen add-back treatment in endometriosis, breast cancer or prostate cancer. In accordance with a preferred embodiment, the solid dosage unit is used in female hormone replacement therapy or female contraception. Most preferably, the solid dosage is used in female hormone replacement therapy, especially to treat vulvovaginal atrophy and/or vasomotor symptoms.

The use of the solid dosage unit in medical treatment, in female hormone replacement therapy or in female contraception, typically comprises sublingual, buccal or sublabial administration of the dosage unit to provide at least 0.1 mg, more preferably 0.5-100 mg and most preferably 1-40 mg of the estetrol component.

To treat vulvovaginal atrophy the dosage unit is preferably administered in an amount sufficient to provide at least 0.1 mg of the estetrol component. More preferably, the administered dosage unit provides at least 0.5 mg, most preferably at least 1 mg of the estetrol component. In the treatment of vulvovaginal atrophy the dosage unit is preferably administered in an amount that provides no more than 50 mg, more preferably not more than 20 mg and most preferably not more than 10 mg of the estetrol component. To treat vasomotor symptoms the dosage unit is preferably administered in an amount sufficient to provide at least 0.2 mg of the estetrol component. More preferably, the administered dosage unit provides at least 1 mg, most preferably of at least 2 mg of the estetrol component. In the treatment of vasomotor symptoms the dosage unit is preferably administered in an amount that provides no more than 100 mg, more preferably not more than 40 mg and most preferably not more than 20 mg of the estetrol component.

Typically, these uses of the solid dosage unit comprise once daily administration of the dosage unit during a period of at least 1 week, more preferably of at least 2 weeks. During these periods the solid dosage unit is preferably administered to provide a daily dose of at least 0.05 mg, more preferably of 0.1-40 mg and most preferably of 0.2-20 mg of the estetrol component.

To treat vulvovaginal atrophy the dosage unit is preferably administered to provide a daily dose of at least 0.1 mg of the estetrol component. More preferably, the dosage unit is administered to provide a daily dose of 0.5-20 mg, most preferably of 1-10 mg of the estetrol component.

To treat vasomotor symptoms the dosage unit is preferably administered to provide a daily dose of at least 0.2 mg of the estetrol component. More preferably, the dosage unit is administered to provide a daily dose of 1-40 mg, most preferably 2-20 mg of the estetrol component.

Yet another aspect of the invention relates to a process of preparing a solid dosage unit as described herein before, said process comprising the steps of:

-   -   providing carrier particles having a volume weighted average         particle size of 10 μm to 400 μm;     -   providing a loading liquid comprising at least 50 wt. % of         organic solvent selected from methanol, ethanol, iso-propanol,         acetone and combinations thereof; 1-50 wt. % of estetrol         component and 0-49 wt. % of one or more other pharmaceutically         acceptable ingredients;     -   mixing 1 part by weight of the loading liquid with 0.5-20 parts         by weight of the carrier particles to produce wet particles;     -   removing organic solvent from the wet particles to produce         loaded particles;     -   optionally mixing the loaded particles with one or more         tabletting excipients; and     -   forming the loaded particles or the mixture of the loaded         particles and the one or more tabletting excipients into a solid         dosage unit.

The carrier particles used in the preparation of the loaded particles preferably contain water-soluble carbohydrate as defined herein before. Preferably, said water-soluble carbohydrate constitutes at least 50 wt. %, more preferably at least 80 wt. % and most preferably at least 90 wt. % of the carrier particles.

According to one preferred embodiment, the carrier particles contain at least 20 wt. %, more preferably at least 30 wt. % and most preferably at least 40 wt. % mannitol.

According to one preferred embodiment, the carrier particles contain at least 10 wt. %, more preferably at least 20 wt. % and most preferably at least 30 wt. % lactose.

The mixing of the loading liquid with the carrier particles and drying of wet particles in the present process may yield loaded particles in the form of coated particles and/or granules. Coated particles comprise a single carrier particle, whereas granules contain two or more carrier particles. Preferably, the loaded particles produced in the present process are granules that, on average, contain more than 2 carrier particles.

The loading liquid employed in the present process preferably contains at least 60 wt. %, more preferably at least 80 wt. % of organic solvent selected from methanol, ethanol, iso-propanol, acetone and combinations thereof. Preferably, the organic solvent is selected from ethanol, iso-propanol and combinations thereof. Most preferably, the organic solvent is ethanol.

The loading liquid preferably contains at least 60 wt. %, more preferably at least 70 wt. % and most preferably at least 80 wt. % ethanol.

Besides organic solvent, the loading liquid may suitably contain other polar solvent, e.g. water.

According to a particularly preferred embodiment of the present process more than 90 wt. % of the estetrol component in the loading liquid is dissolved when the loading liquid is mixed with the carrier particles. More preferably at least 95 wt. % and most preferably at least 98 wt. % of the estetrol component in the loading liquid is dissolved when the loading liquid is mixed with the carrier particles.

The loading liquid employed in the present process typically contains 2-40 wt. % of the estetrol component. More preferably the loading liquid contains 5-35 wt. % of the estetrol component. Most preferably, the loading liquid contains 10-30 wt. % of the estetrol component.

Examples of the one or more other pharmaceutically acceptable ingredients that are optionally present in the loading liquid besides the estetrol component include binders, mucoadhesive agents, colouring, flavouring and combinations thereof.

The loading liquid preferably contains 0.5-40 wt. %, more preferably 1-25 wt. % and most preferably 2-20 wt. % of binder as defined herein before.

In the present process organic solvent is removed from the wet particles after the mixing of the carrier particles with the loading liquid has been completed. In a preferred embodiment reduced pressure is applied (e.g. less than 200 mbar) to facilitate the removal of organic solvent during production of the loaded particles. Typically, organic solvent is removed at an elevated temperature of more than 40° C., more preferably of more than 50° C.

The loaded particles obtained after removal of organic solvent typically contain less than 10 wt. % of organic solvent. More preferably, the loaded particles contain less than 5 wt. %, and most preferably less than 2 wt. % organic solvent.

The wet particles are preferably produced by mixing the carrier particles with the loading liquid in a high shear granulator, a low shear granulator or a fluidized bed granulator. Most preferably, the wet particles are prepared in fluidized bed granulator.

According to a particularly preferred embodiment of the present process the organic solvent is removed from the wet particles in a fluidized bed granulator.

In the present process the wet particles are preferably prepared by mixing the loading liquid with the carrier particles in a weight ratio that is in the range of 1:0.8 to 1:12. Even more preferably, the loading liquid and the carrier particles are mixed in a weight ratio that is in the range of 1:1 to 1:10, most preferably in the range of 1:1.5 to 1:5. The aforementioned weight ratio is calculated on the basis of the total amount of carrier particles and loading liquid that is used in the preparation of the loaded particles.

The loaded particles produced in the present process typically have a volume weighted average diameter in the range of 100-4,000 μm. More preferably, the volume weighted average diameter of these loaded particles is in the range of 200-1,000 μm, most preferably in the range of 200-600 μm.

Examples of tabletting excipients that may suitably be employed in the present process include filler, disintegrating agents, mucoadhesive agents, flavouring, colouring, glidents, lubricants and combinations thereof.

The tabletting excipients employed in the present process preferably contain, calculated by weight of said tabletting excipients, at least 50 wt. %, more preferably at least 70 wt. % of one or more excipients selected from lactose, mannitol, xylitol, microcrystalline cellulose, starch, croscarmellose sodium, polyvinyl pyrrolidone and combinations thereof. According to one particularly preferred embodiment, the tabletting excipients contain at least 40 wt. % mannitol. In accordance with another preferred embodiment, the tabletting excipients contain at least 30 wt. % lactose.

According to another preferred embodiment, the tabletting excipients contain 0.1-15% by weight of the dosage unit of a disintegrating agent selected from modified starches, crosslinked polyvinylpyrrolidone, crosslinked carmellose and combinations thereof. More preferably, the disintegrating agent is applied in a concentration of 0.2-10%, most preferably 1-5% by weight of the dosage unit.

Preferably, in the present process the loaded particles are mixed with the one or more tabletting excipients in a weight ratio that is the range of 1:4 to 9:1, more preferably in the range of 1:2.5 to 3:1 and most preferably of 1:1.5 to 1.5 to 1.

In the present process the solid dosage unit may suitably be formed by direct compression or compression moulding. Most preferably, the solid dosage unit is from by direct compression.

The solid dosage units obtained by the present method can be packaged in different ways. Preferably, the dosage units are packaged in a blister pack containing at least 14 dosage units.

The invention is further illustrated by means of the following non-limiting examples.

EXAMPLES Dissolution Test

The dissolution test described below can be used to study the dissolution behaviour of orodispersible dosage units.

Dissolution Apparatus

-   -   Paddle and basket dissolution tester VanKel VK 7010 or VK 7025,         autosampler VK 8000, 1000 mL dissolution vessels and porous         micron filters (35 pin)

Dissolution Medium

-   -   Transfer 9,000 ml of demineralised water into a volumetric flask         of 10,000 ml.     -   Add 68.05 g of KH₂PO₄ and 8.96 g NaOH and stir the solution         until everything is dissolved.     -   Mix the solution and adjust the pH to 6.8 with NaOH or         phosphoric acid, if necessary and make up to volume with         demineralised water.

Dissolution Procedure

-   -   Transfer 900 ml of Dissolution Medium into each vessel of the         paddle apparatus.     -   Assemble the apparatus, warm the medium to 37±0.5° C., and         remove the thermometer.     -   Place in each of the six vessels one tablet at the bottom before         starting the rotation of the paddles.     -   Start the rotation of the paddles immediately.     -   Use a stirring speed of 50 rpm.     -   Take samples of 5 ml from the dissolution vessels after 5, 10,         20, 30, 45, 60, 75 and 90 minutes for a complete dissolution         profile. Take the sample from a position midway between the         surface of the dissolution medium and the top of the paddle         blade and not less than 10 mm from the vessel wall. The removed         dissolution volume is not replaced by fresh dissolution medium.

Estetrol concentrations in the samples were determined by means of HPLC using estetrol stock solutions as a reference.

Preparation of Mobile Phase (MP) Phosphate Buffer

-   -   Transfer 1.15 g of NH₄H₂PO₄ (10 mM) into a 1,000 ml of         demineralised water, dissolve it and adjust the pH to 3.0 with         phosphoric acid.

HPLC Apparatus

-   -   Alliance 2695 Separations module consisting of a quaternary         solvent delivery system, a variable volume injector, a         temperature controlled autosampler, column thermostat and         Photodiode array detector 2996 (all by Waters)     -   Analytical colunm: Symmetry C18, 3.9×150 mm, dp=5 μm (ex Waters)     -   Guard column: Security guard columg C18, 4×3 mm (Phenomenex)     -   Flow: 1.0 mL/min     -   Detection: UV @ 280 nm     -   Column temperature: 30° C.     -   Autosampler temperature: 10° C.     -   Injection volume: 100 μL     -   Run time: 12 min

Elution Gradient

Time (min) Acetonitrile (%) Phosphate buffer (%) 0 20 80 9 75 25 10 20 80 12 20 80

The dissolution tests are conducted in triplicate.

Particle Size Measurements

Particle size distribution of estetrol monohydrate is performed using a MALVERN MASTERSIZER MICROPLUS laser particle size analyzer.

Preparation of Dispersion Medium:

-   -   Weigh 1 g of estetrol monohydrate and 1 g of sorbitan trioleate         into a flask.     -   Add 1 litre of n-hexane and mix for at least 1 hour at room         temperature     -   Filter through a 0.45 μm filter.

Sample Preparation:

-   -   Put 100 mg of sample in a 25 mL beaker.     -   Add some drops of dispersion medium.     -   Mix carefully with a glass rod to suspend well the powder.     -   Add 10 mL of dispersion medium.     -   Perform the analysis with the sample dispersion unit's speed at         3000-3500 rpm.

Analysis:

Particle size measurements are performed three times using the same dispersion. The final result is obtained by averaging the results of the three determinations.

Example 1

A sublingual tablet is prepared by means of the procedure described below.

A granulation mixture having the composition shown in Table 1 is prepared by dry blending of the ingredients.

TABLE 1 Ingredients Wt. % Mannitol 50 Lactose 35 Microcrystalline cellulose 10 Sodium croscarmellose 5

An alcoholic granulation liquid containing estetrol and having the composition shown in Table 2 is prepared by dispersing milled estetrol and ethylcellulose in ethanol under gentle stirring.

TABLE 2 Ingredients Wt. % Milled estetrol ¹ 30.3 Ethylcellulose 10.0 Ethanol 59.7 ¹ D_((v; 0.5)): 15 μm

The granulation mixture is granulated in a high shear granulator by gradually adding the alcoholic granulation liquid. The total amount of loading liquid added amounts to 50% by weight of the granulation mixture.

The granulate so obtained is dried in the curve of the high granulator under reduced pressure and at 30° C.

A tabletting mixture having the composition shown in Table 3 is prepared by mixing the dry granulate with the excipients.

TABLE 3 Ingredients Wt. % Estetrol containing granulate 99 Flavour 0.5 Magnesium stearate 0.5

The tabletting mixture is compressed into 80 mg round tablets with a diameter of 6.5 mm. The estetrol content of these tablets is 10 mg.

Example 2

A sublingual tablet is prepared by means of the procedure described below and illustrated in FIG. 1.

The target amount of estetrol per tablet was 10 mg and the target weight for the tablets was 80 mg.

The binder (ethyl cellulose) was dissolved in ethanol until a binder solution of 15% ethyl cellulose was obtained. Estetrol was added and mixed, and additional ethanol was added to obtain a diluted suspension. Other excipients were screened over 800 μm screen. Granulation was started by adding the binder solution to the dry mixture consisting of the remaining intragranular excipients (batchsize ±100 gram). A granulate was formed after 30 seconds of mixing, and the complete granulate was formed after 1.5 minute of granulation in total (suitable granulate as detected visually).

After drying and milling, magnesium stearate was added and mixed for 3 minutes. Compression was executed using a single punch machine equipped with 6 mm punches in order to obtain 80 mg tablets.

No problems were detected during the experiments, flowability of the blend was good and no sticking was observed.

Disintegration time was quantified according to the known protocol described in Ph. Eur. 2.9.1 (“Disintegration of tablets and capsules”), and in USP <701> (“Disintegration”) using water as the specified liquid.

Hardness was measured using the known protocol described in Ph. Eur. 2.9.8 (“Resistance to crushing of tablets”).

The final formulation and corresponding tablet results can be found in Tables 4 and 5 below.

TABLE 4 details of the formulation in Wt. % Formulation Wt. % Intragranular Milled Estetrol ¹ 12.51 Mannitol 40.95 Lactose 29.43 MCC 8.26 Sodium crosscarmellose 4.10 Ethylcellulose 4.11 Ethanol (per 100 gram granulation mixture) 64 Extragranular Magnesium stearate 0.62 ¹ D_((v; 0.5)) = 15 μm

TABLE 5 experimentally determined characteristics of the Tablets Test (average result of 6 samples) Disintegration time Hardness Weight (min:sec) (N) (mg) 0:31 34.47 78.87

It can be seen that the tablets were obtained with a final weight close to their target weight and that the disintegration time was very short, in accordance with the intended sublingual, buccal or sublabial administration route for these tablets.

Finally, the hardness was within a very acceptable range.

Example 3

A randomized, open-label, two-period, cross-over, pharmacokinetic study is conducted to compare sublingual bioavailability of 10 mg estetrol administered in one 80 mg tablet with oral availability of estetrol contained in a 83 mg tablet containing 10 mg estetrol. These tablets are administered sublingually and orally to healthy female volunteers under fasting conditions.

Ten healthy female subjects are selected on the basis of the following criteria: age of 45-65 years (inclusive), nonsmokers or past smokers (at least 6 months before dosing), body-mass index (BMI)=18.5 to 30 kg/m² (inclusive at the time of the screening).

At the start of the first and the second period of the study, between 07:00 am and 07:28 am, 5 subjects receive a single dose of the sublingual formulation of estetrol by administering one estetrol tablet (tablet weight 80 mg; 10 mg estetrol) and 5 subjects receive a single oral dose of the oral estetrol formulation by administering one estetrol tablet (tablet weight 83 mg; 10 mg estetrol), ingested together with 200 ml water.

Subjects are required to fast for at least 10 hours prior to tablet administration and for at least 4 hours after administration. Drinking of water or beverages is not permitted within 1 hour before the drug administration. Subjects receive 200 ml of water 1 hour prior to and 2 hours after tablet administration. Subjects are free to drink water and fruit tea from 4 hours following the tablet administration. Standardized meals are provided 10.5 hours before and 4, 6, 9, and 13 hours after tablet administration.

The sequence of events that occurs during the first and second period is shown in Table 6:

TABLE 6 Event First period Day 1 Confinement from 19:00 Day 2 Dosing, blood and urine sampling, confinement Day 3 Exit procedure, confinement till 8 am Days 4-8 Return visits Days 9-13 Wash out Second period Day 14 Confinement from 19:00 Day 15 Dosing, blood and urine sampling, confinement Day 16 Exit procedure, confinement till 8 am Days 17-21 Return visits Days 22-26 Wash out Day 27 Administration of a progestin Day 28 Phone call, progestin withdrawal test check

The blood and urine sampling schedule used in this study is shown in Table 7.

TABLE 7 Blood Blood collection (4 ml) is performed prior to administration of sampling the tablet (0), and subsequently 0:10, 0:15, 0:20, 0:25, 0:30, 0:35, 0:40, 0:45, 0:50, 0:55, 1:00, 1:10, 1:20, 1:30, 2, 3, 4, 6, 10, 16, 24, 48, 72, 96, 120, 144 hours after administration. Total number of blood collections in each period is 27. Urine Urine collection is performed prior to administration of the sampling tablet and 2, 4, 8, 12, 24, 48, 72, 96, 120 and 144 hours after administration. Total number of urine collections in each period is 11.

The estetrol concentration in the collected blood samples is determined by means of HPLC/MS/MS. The concentrations of glucuronided estetrol (D-ring) in the urine samples is also determined with the help of HPLC/MS/MS.

Results of these analyses show that the bioavailability of sublingually administered estetrol is comparable or even superior to orally administered estetrol. Furthermore, the data suggest that sublingually administered estetrol has an earlier bioavailability compared to orally administered estetrol. Sublingual estetrol has less impact on a liver function parameter. 

1-33. (canceled)
 34. A process of making an orodispersible solid pharmaceutical dosage unit having a weight between 30 and 1,000 mg and containing at least 100 μg of an estetrol component selected from one or more of estetrol and estetrol esters, comprising: providing carrier particles having a volume weighted average particle size of 10 μm to 400 μm; providing a loading liquid comprising an organic solvent in an amount of at least 50 wt. % selected from one or more of methanol, ethanol, isopropanol, and acetone; the estetrol component in an amount of 1-50 wt. %, and one or more other pharmaceutically acceptable ingredients in an amount of 0-49 wt. %; mixing 1 part by weight of the loading liquid with 0.5-20 parts by weight of the carrier particles to produce wet particles; removing organic solvent from the wet particles to produce loaded particles; optionally, mixing the loaded particles with one or more tabletting excipients to produce a mixture; and forming the loaded particles or the mixture into a solid dosage unit having a weight between 30 and 1,000 mg and containing at least 100 μg of the estetrol component.
 35. The process according to claim 34, wherein the carrier particles contain a water-soluble carbohydrate in an amount of at least 30 wt. %, selected from one or more of monosaccharides, disaccharides, trisaccharides, and C₄-C₁₂ sugar alcohols.
 36. The process according to claim 35, wherein the carrier particles contain the water-soluble carbohydrate in an amount of at least 50 wt. %.
 37. The process according to claim 35, wherein the water-soluble carbohydrate is selected from one or more of maltose, fructose, sucrose, lactose, glucose, galactose, trehalose, xylitol, sorbitol, erythritol, maltitol, and mannitol.
 38. The process according to claim 35, wherein the carrier particles contain mannitol in an amount of at least 20 wt. %.
 39. The process according to claim 35, wherein the carrier particles contain lactose in an amount of at least 10 wt. %.
 40. The process according to claim 34, wherein more than 90 wt. % of the estetrol component in the loading liquid is dissolved when the loading liquid is mixed with the carrier particles.
 41. The process according to claim 34, wherein the estetrol component is present in the loading liquid in an amount of 2-40 wt. %.
 42. The process according to claim 34, wherein the loading liquid contains a binder in an amount of 0.5-40 wt. % selected from one or more of cellulose derivatives and polyethylene glycol.
 43. The process according to claim 42, wherein the binder is ethylcellulose.
 44. The process according to claim 34, wherein the wet particles are produced by combining the loading liquid and the carrier particles in a high shear granulator, a low shear granulator, or a fluidized bed granulator.
 45. The process according to claim 34, wherein the organic solvent is removed from the wet particles in a fluidized bed granulator.
 46. The process according to claim 34, wherein the loading liquid contains at least 60 wt. % ethanol.
 47. The process according to claim 34, wherein the wet particles are prepared by mixing the loading liquid with the carrier particles in a weight ratio that is in the range of 1:0.8 to 1:12.
 48. The process according to claim 34, wherein the loaded particles have a volume mean diameter in a range of from 100 to 4,000 μm.
 49. The process according to claim 34, wherein the tabletting excipients contain a disintegrating agent in an amount of 0-20% by weight of the dosage unit, selected from one or more of modified starches, crosslinked polyvinylpyrrolidone, and crosslinked carmellose.
 50. The process according to claim 34, wherein the one or more tabletting excipients comprise at least 30% by weight of the dosage unit of one or more selected from lactose, mannitol, xylitol, microcrystalline cellulose, starch, croscarmellose sodium, and polyvinyl pyrrolidone.
 51. The process according to claim 34, wherein the dosage unit is formed by direct compression or compression molding.
 52. The process according to claim 34, wherein the dosage unit has a weight between 40 and 500 mg.
 53. The process according to claim 34, wherein the dosage unit contains 0.3-100 mg of the estetrol component.
 54. The process according to claim 34, wherein the estetrol component is estetrol.
 55. An orodispersible solid pharmaceutical dosage unit made by the process of claim
 34. 56. A method of administering an estetrol component to a subject in need thereof, comprising administering a solid dosage unit according to claim 55 to the subject by sublingual, buccal or sublabial administration.
 57. The method of claim 56, wherein the administering is by once daily administration during a period of at least 1 week.
 58. The method of claim 56, wherein the method is for providing female hormone replacement therapy.
 59. The method of claim 56, wherein the method is for providing female contraception. 